Non-specific lipid transfer protein 1 (Pru p 3) (Pru p 3)

Non-specific lipid transfer protein 1 (Pru p 3) is the primary allergen in peach (Prunus persica) and a member of the nsLTP family (UniProt P81402). It is a small, 9 kDa protein with a compact structure of four alpha-helices stabilized by four disulfide bonds, forming a central hydrophobic cavity (PubMed: 22404458). This cavity binds hydrophobic lipid ligands, such as phytosphingosine, which function as pro-inflammatory adjuvants that recruit invariant Natural Killer T (iNKT) cells and enhance the allergic sensitization process (PubMed: 25151377). Pru p 3 is highly resistant to heat and gastric digestion, allowing it to act as a primary sensitizer through the gut (PubMed: 10851112). It is the main target for component-resolved diagnosis and allergen-specific immunotherapy in patients suffering from peach allergy and related pollen-food syndromes. The presence of the lipid ligand is essential for the protein's full immunogenic potential, as it stabilizes the fold and provides necessary co-stimulatory signals to the immune system.

Other names

Peach major allergen Pru p 3nsLTP1Lipid transfer protein 1Prunus persica allergen 3

Allergen-specific immunotherapy (AIT) using Pru p 3 aims to induce peripheral immune tolerance by shifting the T-cell response from a Th2-dominated profile to a Treg/Th1-dominated profile. This process leads to the production of blocking IgG4 antibodies and a reduction in IgE-mediated mast cell and basophil degranulation upon subsequent exposure to the allergen.